By Dan Chu
Updated October 14, 1991 12:00 PM

THEY CALL THEMSELVES BIOSPHERIANS—four men, four women, all single, all wearing navy-blue Buck Rogers jumpsuits. Like adventurers off on an extended journey, several of them have spoken wistfully of the people and pleasures they are leaving behind. Linda Leigh, 39, won’t be going horseback riding for a while. Taber MacCallum, 27, will miss Häagen-Dazs ice cream. Said Roy Walford, 67, a divorced father: “I’ll miss my girlfriend and my daughter. People first, then cities like Los Angeles and New York.”

Leigh, MacCallum, Walford and their five colleagues—Mark Nelson, 44; Abigail Ailing, 32; Jane Poynter, 29; Sally Silverstone, 36, and Mark Van Thillo, 30—are out of the social whirl for the duration. On Sept. 26, when a metal door clanged shut behind them at 8:16 A.M., the eight were hermetically sealed into Biosphere 2, an extravagant, 3.15-acre steel-and-glass habitat in the Arizona desert. If all goes according to plan, they won’t come out until Sept. 25, 1993.

Their first days, at least, went well, reported Nelson by phone from inside Biosphere 2: “We’ve been involved in bringing in a good-looking rice harvest.” Nelson told of how Silverstone was knee-deep in a flooded paddy trying to snag a fish while 75 tourists outside watched through the glass. When at last she landed her catch, a cheer went up from the gawking gallery.

Seven years in the creation, Biosphere 2 has attracted its share of skeptics in the scientific community. Critics have questioned the credentials and motives of the tight-knit coterie that dreamed up the project and financed it lavishly. Some have viewed the exercise as nothing more than a stunt, a voyage of discovery that might be, in a strict scientific sense, a trip to nowhere.

For sheer audacity, though. Biosphere 2—the earth itself, in Biospherian-speak, is Biosphere 1—rates high on the gee-whiz scale. Glimmering in the sun near Oracle, Ariz., 30 miles north of Tucson, the rambling geometric construct stands eight stories high at its tallest point. Within its 7 million cubic feet are living quarters, a kitchen, laboratories, maintenance shops and five miniature ecological systems intended to mimic Earth’s own: a rain forest, a desert, a savannah, a marsh and a 25-foot-deep saltwater ocean with machine-made waves.

About 3,800 species of plants (including 140 varieties of food crops) and animals (right down to bugs and worms) have been placed inside Biosphere 2 to create a closed ecosystem in which everything, including oxygen and human waste, is continually recycled. The entire structure is sealed like a tightly corked bottle so that nothing gets in except energy (via sunlight and electrical power) and information (Biospherians can communicate using telephones and computers and, yes, they have cable TV). “Without the air seal,” says Nelson, “Biosphere 2 is just an interesting greenhouse.” Sealed up, supporters claim, Biosphere 2 is an independent, self-regenerating life-support system, the perfect lab in which to make controlled studies of some of the natural workings in the world outside.

Assisted by 1,000 sensors that monitor air and water throughout the structure, the eight Biospherians are charged with keeping the process functioning and in balance. They will eat only the foods that they grow and raise themselves. In the event of serious illness, a patient can be taken out through an air lock.

Oddly, though all the Biospherians worry about technical breakdowns—the cooling system, say—they seem blithely unconcerned about how they will get along with each other during the 731 days—and nights. Each has a comfortably furnished, dormitory-like apartment to retreat to for privacy. As for the possibility of passion among the pioneers, “We’ve got four men and four women, all single and healthy,” Silverstone has said. “So I don’t think you can discount the possibility of sexual encounters.”

While the roster of Biospherians has shifted over time, all on the final list have worked closely on the project from the start. Walford, the eldest and most accomplished among them, is an M.D., a UCLA professor of pathology and a noted authority on human aging. MacCallum, the youngest, never finished college and taught English in Japan. Nelson has a degree in philosophy from Dartmouth and was one of the originators of the Biosphere concept. Leigh holds a botany and field ecology degree from Washington’s Evergreen State College and worked for a time with the Arizona Nature Conservancy. Alling is a marine biologist with a master’s from Yale, and Poynter was once an art gallery assistant in London. Her fellow Briton, Silverstone, has worked in service projects in Africa and India, while Van Thillo, a Belgian, has a knack for handling machinery.

The one thing shared by everyone directly involved in Biosphere 2 is an association with John Allen, a metallurgist turned eccentric visionary, who is the project’s spiritual father. Two decades ago Allen, 62, gathered followers at a New Mexico ranch and began preaching a message that mixed ecology and consciousness-raising. Over the years Allen’s group has spawned such projects as a concrete-hulled replica of a Chinese junk that sailed the ocean for marine research, and a 300,000-acre cattle station in the Australian outback. As for Biosphere 2, Allen neither confirms nor denies speculation that it is a spin-off from his longtime interests in space colonization.

None of Allen’s grand-scale schemes might have gotten off the ground without the deep pockets of Edward Bass, 46, billionaire scion of the Texas oil family, who has borne practically all of the estimated $150 million cost of the latest undertaking. Bass insists that Biosphere 2 is also a test of private enterprise and will eventually turn a profit from the sale of technologies—such as air-cleaning devices—that might be patented and sold. So far, though, its main source of income, other than Bass, is its status as a roadside attraction. With some 600 sightseers visiting daily—at around $10 a head—Biosphere 2 may soon become second in popularity to the Grand Canyon among Arizona tourist sites.

For now, mainstream scientists seem most comfortable with a wait-and-see attitude toward Biosphere 2. “It can’t be called much of a scientific experiment, because you can’t replicate it,” says Ronald Carroll, associate director of the University of Georgia’s Institute of Ecology, referring to the requirement in rigorous science for independent verification of research. “But it’s a very interesting engineering project.” The Biospherians themselves realize that a multitude of things could go wrong to cut short their experiment, and Walford, for one, has conceded that he doesn’t know “exactly what science will come out of it.” Says Nelson: “Let’s not overplay Biosphere 2. It’s not going to solve the world’s problems.”

At the very least, though, it may provide, during the next two years, a welcome alternative to Star Trek reruns.